About the UNC Emergency Alert System Siren
The University has installed a new UNC Emergency Alert System Siren, which will sound during an immediate life-threatening situation such as an armed and dangerous person in the area, a major chemical spill or hazard, or a tornado.
In an emergency, the siren sound will be followed by public address announcements providing specific instructions including: 
- Seek shelter inside now.
- Stay until further notice.
When the danger is over, a second siren sound and announcement will signal: all clear; resume regular activities.
An all clear signal may come quickly, or it could take several hours. The timing will depend on how fast emergency responders can determine that a threat is over.
Activation of the siren system coincides with the spring 2008 launch of Alert Carolina, an educational initiative for the University community covering campus safety issues and what you should do in an emergency.
When the siren will sound
When the siren sounds, you face an immediate life-threatening situation. There are three main examples of emergencies when the siren will sound:
Armed and dangerous person in the area.
- Seek shelter inside now.
- Close windows and doors.
- Stay until further notice.
Major chemical spill/hazard.
- Seek shelter inside now.
- Close windows and doors.
- Stay until further notice.
Tornado sighted in the area.
- Seek shelter inside or take cover immediately.
- Stay away from windows and doors.
- Stay until further notice.
When the emergency is over, expect to hear the sirens sound with an announcement of an all clear; resume regular activities.
Locations
People on or near campus will hear the siren when it sounds from four locations:
- Hinton James Residence Hall off Manning Drive.
- Gary R. Tomkins Chilled Water Operations Center behind the Dogwood Parking Deck.
- Winston Residence Hall at the corner of Raleigh Street and South Road.
- At University buildings and support facilities on Airport Drive north of main campus off Martin Luther King Boulevard.
Other Information Sources
When the siren sounds, the University will provide information and updates as quickly as possible. But, depending on the situation, it could take time to share additional details.
Sources of information for the University community include alertcarolina.unc.edu, a new Web site. alertcarolina.unc.edu supports campus communication initiatives including the UNC Emergency Alert System and additional capability for the University to send emergency text messages.
These new tools — the siren system, text messages and the new Web site — provide information to the campus more quickly than in the past.
But the University will also continue to use a combination of other means to share information including email and telephone voice mail, the Adverse Weather and Emergency Phone Line, 843-1234, for recorded information, the University Access Channel (Chapel Hill Time Warner Cable Channel 4), and campus or local media.
Technology
The University's siren system was purchased last spring from Federal Signal Corp., following about two years of discussion and planning. The system was designed to deliver high-intensity warning signals over a large area using omni-directional speakers. Those speakers are capable of producing a high sound level while making moderate demands on the battery power source. Activation is by dedicated radio frequency and the sirens run on batteries that are continuously charged by a solar panel on each siren pole. These characteristics ensure continuous operation regardless of power outages.
Sounds
People on or near campus can expect to hear two different sounds — one to signal immediate action (such as go or remain inside) and another to indicate all clear. Testing will determine the exact tones to be used. When finalized, audio samples of the tones will be added to this online fact sheet.
Distance for the Sounds
Until testing is completed, it is unclear how far the siren sound will carry off the main campus and near UNC facilities off Airport Drive. Federal Signal Corp.'s product specifications indicated that the signal from each of the four siren locations could be expected to carry approximately one-quarter to one-half a mile. The system is designed to be most effective for people outside. Many people inside buildings or in cars or vehicles likely will not hear the siren sound.
Activation
The UNC Department of Public Safety will activate the siren system based on conditions on campus or that emergency officials believe will affect campus. The Information Technology Services Control Center can also activate the siren on behalf of public safety if conditions warrant. The siren will sound only in an immediate life-threatening situation or during testing.
Testing
The University plans to test the siren system regularly. The corresponding public address announcement will say, “This is a test of the UNC Emergency Alert System. This is only a test.” The first full-volume test was conducted Dec. 19, 2007. A second full-volume test is planned early in the spring 2008 semester. Tests will be announced in advance to the campus community and nearby neighbors.